/**
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.hadoop.hive.ql.udf;

import org.apache.hadoop.hive.ql.exec.UDAF;
import org.apache.hadoop.hive.ql.exec.UDAFEvaluator;


public class UDAFCount extends UDAF implements UDAFEvaluator {

  private long mCount;
  
  public UDAFCount() {
    super();
    init();
  }

  public void init() {
    mCount = 0;
  }
  
  public boolean iterate(Object o) {
    // Our SerDe between map/reduce boundary may convert MetadataTypedSerDe to 
    if (o != null && !o.equals("")) {
      mCount ++;
    }
    return true;
  }

  public Long terminatePartial() {
    return Long.valueOf(mCount);
  }

  public boolean merge(Long count) {
    mCount += count;
    return true;
  }

  public Long terminate() {
    return Long.valueOf(mCount);
  }

}
